6533b870fe1ef96bd12d02fe
RESEARCH PRODUCT
Search for pair produced neutralinos in events with photons and missing energy from e+e− collisions at S(1/2) = 130-GeV to 183-GeV
Delphi CollaborationReyes Alemany FernándezSusana Cabrera UrbánMaría Victoria Castillo GiménezM. ColomerEduardo Cortina GilAntonio Ferrer SoriaJuan A. Fuster VerdúCarmen García GarcíaInés Gil BotellaJuan José Hernández ReyEmilio Higón RodríguezFernando Martínez VidalSergio Navas ConchaS. OrtuñoJosé Salt Cairolssubject
High Energy Physics::PhenomenologyHigh Energy Physics::ExperimentFísica nuclearPartícules (Física nuclear)description
The events with two photons and missing (transverse) energy collected by the DELPHI detector at centre-of-mass energies between 130~GeV and 183~GeV have been studied to search for processes of the type e+e−→YY with the subsequent decay Y→Xγ, where X is an undetectable neutral particle. Reactions of this kind are expected in supersymmetric models, where the Y particle can be either the lightest neutralino, decaying to a photon and a gravitino, or the next-to-lightest neutralino, decaying to a photon and the lightest neutralino. To study the case of long-lived Y particles, a search for single-photon events with the reconstructed photon axis pointing far from the beam interaction region has also been performed. No evidence for a deviation from Standard Model expectations has been observed in the data and upper limits have been derived on the signal cross-section as a function of the the X and Y masses and of the Y mean decay path.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1999-01-01 |